Weird changes in object mode after editing in edit mode
If you still wish to repair the model, here is how:
Tab into edit mode and select the head key under object data (The Upside down Triangle with vertices).
Hide all the other keys if they are not already.
Your object should look normal, now toggle on and off the legs key and select the affected vertices.
Once they are all selected, delete them. (X &gt; Vertices)
Hide every key except basis and select it. Now rebuild the faces. This is fairly easy with edge select and press  F.
Double check your weight painting and your all good.